Mobile x-ray devices with C-arms are used frequently in surgical interventions in operating rooms. The extensive mobility of the C-arm x-ray systems allows staff to move the C-arm x-ray system away from and back to the patient on the operating table while an operation is in progress. It is beneficial, especially during use in small operating rooms, not to have to move the relatively heavy C-arm x-ray systems in the entirety too often. It is preferable to move the C-arm, having an x-ray emitter and x-ray detector, only within certain confines, rather than the entire C-arm system. Positions which have already been assumed by the C-arm system can be reassumed automatically and precisely.
U.S. Pat. No. 6,609,826 B1 describes the way in which a C-arm can be moved horizontally to and in parallel with a patient support. U.S. Pat. No. 6,609,826 B1 discloses a moving apparatus between a C-arm and a retaining device. The C-arm is moveable in a horizontal direction at right angles to one arm. However, the parallel linear guides used and the weight of the C-arm can cause the moving apparatus to jam as a consequence of the unfavorable leverage ratio between the displacement force applied and the distance to the linear guides.